A couple of years ago, her son, Tim, now 16, grumbled that his mom was serving chicken far too often.

“I said, ‘Well, you have some nerve to complain,’ ’’ Commerford recalled as she prepared to tackle Tunisia from her cozy Holliston kitchen on a recent winter morning.

Her son’s antidote to the poultry problem was to cook a dish from one new country every week, but Commerford, 53, didn’t immediately hop on board.

A couple of months later she was watching “Julie & Julia,’’ a movie about a book about a blog, which grew out of one woman’s attempt to spend a year cooking every recipe in Julia Child’s legendary tome “Mastering the Art of French Cooking.’’

Tim came in and started watching the movie, and her blog “What’s Cooking in Your World?’’ was born.

Commerford, a self-employed special education advocate, is cooking her way through 193 countries. She started with Afghanistan in April 2010, and expects to complete her culinary journey this spring with Zimbabwe. Her progress can be tracked online at www.whatscookinginyourworld.com.

Sometimes the ingredients send Commerford on a gastronomic scavenger hunt. For Andorra, Commerford had to find wild boar, which she did over the Internet at an exotic meat company in New Jersey. At Savenor’s Market in Cambridge, she tracked down ostrich for recipes from Swaziland and South Africa, and alligator for a dish from Namibia. Recipes from the Middle East often mean a trip to Arax Market in Watertown, and H Mart in Burlington has become her source for Asian provisions.

“Sourcing stuff is fun,’’ she said. “But mostly I go to Market Basket. I can find almost everything I need at Market Basket.’’

Friends sometimes join in her culinary wanderlust. Ben Wood, whom she described as her husband’s best friend and her own “foodie soulmate,’’ brought over some tamarind for a dish from Trinidad and Tobago, which she called “Doubles, barra with channa and cucumber chutney’’ (i.e., sandwiches with chickpeas and cucumbers).

Wood showed her how to take the seeds out of the tamarind and peel it. He said he’s enjoyed several good meals thanks to Commerford’s project.

“I think what really stands out is the way she cooks,’’ said Wood, a Milford resident. “She tries to be as traditional as possible.’’

She has even dug a fire pit in her backyard for some African meals, which Wood said was a pretty impressive effort for authenticity.

Commerford grew up mostly in Cambridge, but spent a couple of years as a youngster in Paris with her mother, who she said is an “amazing home cook.’’

One of her fondest food memories is of her daily chore, at age 6, walking to get a fresh baguette from a nearby bakery, where she befriended the owners.

“They would let me pick out a mini éclair every day I went there,’’ she said. “Then I’d walk home with the baguette, and I’d always take a bite off the top of it. It was still warm.’’

Commerford’s endeavor seems like the kind of project that would be a lot easier to start than to stick with, but friends say her dedication is no surprise.

“It was just so Sarah,’’ said Marylou Sullivan, a longtime friend who lives in Cambridge. “She just has a lot of energy, and she’s always been creative. I just thought it was one of the coolest things ever.’’

This particular day, the menu hails from Tunisia, and the smell of cinnamon and cloves hints at what is to come, as Commerford chops feta into cubes and readies her tagine on the stove. Then, she pours a dressing of olive oil, vinegar, garlic, and spices over the feta.

“I’ll let it marinate and quick take a picture of it,’’ she said, adding that the food can’t sit long or it won’t photograph well.

The project was about cooking when she started, but it has evolved.

“Initially it was about the food, not the photography. Now it’s morphed into both,’’ she said.

She has upgraded her camera substantially since starting, and has learned some tricks from professional food photographers. To capture her Tunisian blog entry, she takes 84 shots to get the right photo for the completed dish, plus many more for the step-by-step photos.

Recipes come from cookbooks that friends bring her from their travels or from the Internet; she said she tries to find websites based in the dish’s country of origin.

And people e-mail her with suggestions from all over the world, which can also spark some interesting political discussions, she said.

After she made honey cookies from Macedonia, someone from Greece e-mailed her to say Macedonia is part of Greece. (It was part of Yugoslavia before it became an independent country, but neighboring Greece disputes the name of the country because it has a northern province called Macedonia. The United Nations calls it the Former Yugoslav Republic of Macedonia.)

In her blog, Commerford refers to Macedonia as an independent country. She said she doesn’t want the blog to get political, but loves e-meeting people from all over the world. Since she began, she’s had to draw a line across Sudan on her giant wall map of the world to represent one of the world’s newest countries, South Sudan.

It’s been an incredible geography lesson, she said, and it definitely makes her look at international news a little differently, since she feels like she’s gotten to know these countries.

“It’s a really big, colorful, spicy world,’’ said Commerford. “We all have to eat.’’